Metallurgical furnace



June 24, 1930. c s m I 1,766,110

METALLURG I CAL FURNACE Filed Dec. 12, 1928 2 Sheets-Sheet l INVENTQR.

Ozzie C Cur/z a? June 24, 1930. D. CUSHING 1,766,110

METALLURGICAL: FURNACE Y Filed Dec. 12, 1928 2 Sheets- Sheet 2 INVENTOR. 17022; e6 C'uwkz 2 preferably closed by a glass orinica disc85. Each cap 31 may also be provided with a slot I 36 and binding screw 37 by which said cap may be held in desired angular adjustment.

'Thescrews 37 may be taken out and the caps 31 maybe removed if access to the 'tuyere'openings is desired. It is sometimes desirable to reduce the number of. tuyere Openings in use, and the removal of the caps 31 permitsselected tuyeres to be conveniently; j, closed by insertingtemporaryplugs therein.

The lower part of thefurnace; is ofa special construction which forms thesubject matter .of "the. claims retained 1n my original application. :end of the cupola or body portion 10 of my 7 improved furnace Iprovide a bottom'me'm- 'ber 40, pivoted at 41 to bearing members or For closing the lower cars 42 extending downward'from the annu- The member is provided with an I ibe described. The outwardly extending rim portion 461- engages the annular base mem- "ber 10 and forms a sealing member therefor.

' A cross bar 48Qextends between the arms 49 on which the vbottommemberis pivoted, and the member 40 may be swung upward to operative position by placing a lever 50 under the member 40-an d over the crossbar I fireebrick 54 fitted within the circular flange '45 and having grooves 55in their edge. portionsadapted to fit over. the rib 47 layer 48; YVhen-the bottomniember 40has been movedto raised position, a postor brace 51 maybe inserted to hold the ,c member 40 in such raised or operative position. A chain 52 may be'providedito limit the swmgmember. 1 J

ing downward movement ofithe bottom-'- ao r v'VVhen inoperation, the bottom member 40 supports a lining preferably formed of of heat insulating material 56 is preferably provided between'the bottom member 40 and v the bricks 54. I Thelining is thus retained firmly in operative positionfby the rib- 47 flange 45 by. suitable cement iffdesired.

The bricksxareso firmly secured in posiand may be additionally secured within the "tion; that the bottom "memb g0 Vmay b swungto operative or inoperative'position without'disturbing the lining of the bottom m'ember 40.

to the positionshown inFig; 3, theopening 7 around and above the 'flange'member 45 may 7 60 be closed by a suitable sealing material 57,

such as fire clay or cement, this sealing mait'erial being easily displaced as the bottom 'memb er swings downward. The upper face of-thefire brick54 and of the sealing Ina-1, terial 57 preferably forms an; inclined surutap spout 15. I a V In actual operation, I have found that a face substantially at the level of the tap opening 58, so that the molten metal in the bottom of the furnace may flow freely to the bottom member constructed as above described, is extremely ,well adapted for melt ing non-ferrous metals, especially when in the formof'light chips or scrap. In such a coke of high compressive strength and substantially freefrom impurities. I I i I attain very important advantages by the combination offforcedand natural draft which I have shown and described. V-Vith operationsI preferably use a pitchcoke or this combination, I may close the openings 80 and operate on forced draft entirely, or I I mayuncover theopeningsBO partially, thus modifying and reducing the forcedair pressure to any desired extent. I'may also shutoff the fan F and operate entirely under natural draft, regulating thenatural draft by the angular positions of the caps'31. I

This double control of the air supply has been found extremely useful in carrying out metallurgical operations upon non-ferrous metals, where it is extremely essential that I the draftbe closelyregulated andth'a-t excessive draft be avoided. a I

Having thus described my invention and I the advantages thereof, I doinot wish to be limited to the details herein disclosed otherwise than as set forthin the claims,-but whatI claimis V V '1. A metallurgical furnace comprising a therein, means tosupply air under pressure above. atmospheric to said tuyeres, said cupola having also a passage to admit air under :natural' draft to said tuyeresyland passages, and'tovary the areaofthejairadmitting openings to;sa1d-'passage s. 1

1 cupola havinga plurality of spaced tuyeres I, '105 means to open and close sa1d natural draft 2. A metallurgicalfurnace, comprising a cupola havinga plurality of) spaced tuyres therein, means to supply airunder pressure to saidtuyeres, means to supply air under natural draft to said tuyeres, and meansto vary the proportion of air under pressure and air under natural" draft admitted to a said tuyeres,j said latter means comprising 7 a hollow cylindrical projecting portion having a plurality of openings in the-cylindrical,

outer wall thereof and a cap fitting" said cylindrical projection and having a corre- I I r spending number of openings therein, said After the bottom' member has been raised openings being. separated by imperforate p'ortionsand said cap'being angularly' ad- 'justable on said cylindricaliprojection. i

3.;Means to admit air to a tuyere com-1 prising asubstantially cylindrical structure with a cylindrical outer 'wall provided with" 5 .a plurality of spaced openings, and a regulating cap fitted to said cylindrical wall of said: cylindrical structure. and havingim:

perforate portions of approximately the same Width as the spaced openings in said cylindrical Wall, said perforate portions being spaced apart by openings in said'cap adapted to reglster With SfllCl first named spaced openings. r

4. Means to admitv air .to a tuyere comprising a substantially cylindrical structure with a cylindrical outer Wall provided with a plurality of spacedopenings, and a regulating cap fitted to said cylindrical Wall of said cylindrical structure and having imperforate portions of approximately the same Width as the spaced "openings. in said cylindrical Wall, said imperforate portions being spaced apart by openings in said cap adapted to register With said first named spaced openings, and the end Wall of said cap having provision for fire inspection therein. 1

5. A metallurgical furnace, comprising a cupola having a plurality of spaced tuyeres therein, means to supply air under pressure to said tuyres, means to supply air under naturaljdraft' to said tuyeres, and means'to vary the proportion of air under pressure and. air under natural d raft admitted to said tuyeres, said latter means comprising hollow projecting portions and members adjustably mounted thereon and effective to control the admission of air under natural draft to said tuyeres, said members being also bodily re movable from said hollow projections ,to give access to. said tuyeres. I

In testimony whereof I have hereunto affixed my signature; s

r a DANIEL GUSHING. y 

